1. Technical Field
The present disclosure relates to a motor driving circuit and a fan device, in particular, to a motor driving circuit with power reversal protection and a fan device having the same.
2. Description of Related Art
A motor driver is a necessary modern industrial power transformation device. The motor is capable of transforming electricity into kinetic energy required for driving devices. Conventional motors include DC motors, AC motors, stepping motors, and etc. Motors are often applied to drive one element of the electronic device, for example, blades of the fan device are usually rotated with the motor. Therefore, how to design an efficient motor has become a major objective in the industry. The motor driving circuit is constituted by a stator and a rotor configured opposite to each other. The rotor can rotate with respect to the stator to operate the motor by the magnetic force and magnetic field change, so that the fans configured on the motor are rotated.
Generally speaking, the conventional motor driving circuit has a supply end and a ground end. A power line of a power supply is electrically connected to the supply end, and a ground line of the power supply is electrically connected to the ground end, so that the power supply transmits the power to the motor driving circuit for driving through the supply end, and then operates the motor.
However, when the power line and the ground line of the power supply are connected in reverse, i.e., the ground line electrically connects to the supply end and the power line electrically connects to the ground end, the power supply transmits the power to the motor driving circuit through the ground end, so that the diode of the motor driving circuit is forward biased, to burn out the power supply.
Therefore, if the motor driving circuit can provide a protection mechanism to avoid burning out the power supply when the power line and the ground line of the power supply are connected in reverse, the life time of the power supply can be increased.